1/2-Inch Electric Motor Convertible Arbor - Fits 1/2-Inch Shaft - Attach Grinding, Buffing Wheels - Taiwan Converts 1/2"-diameter motor shafts to 1/2" arbor with right-hand threaded nut Attach buffing, polishing, sanding or grinding wheels up to 1-1/4" width directly to motor Locks on to square edge of shaft with 2 Phillips screws - easier to use than hex screws Total length 2-3/4", threaded length 1-7/8", weight 5 oz. Includes two 1-5/8" washers & 3/4" nut Heavy duty galvanized steel, excellent quality - made in Taiwan. Also in 5/8" shaft size